To find the missing term and complete the sequence, let's analyze the given sequence:

17, 35, 106, 425, ?, 12757

- The sequence does not follow a simple arithmetic or geometric progression.
- Let's examine the differences between consecutive terms:

- The difference between the first and second term is 35 - 17 = 18.
- The difference between the second and third term is 106 - 35 = 71.
- The difference between the third and fourth term is 425 - 106 = 319.
- The difference between the fourth and fifth term is unknown (represented by "?").
- The difference between the fifth and sixth term is 12757 - 425 = 12332.

- It is not immediately clear what pattern or rule is being followed by the differences between consecutive terms. However, let's examine the differences between the differences:

- The difference between the second and first difference is 71 - 18 = 53.
- The difference between the third and second difference is 319 - 71 = 248.
- The difference between the fourth and third difference is unknown (represented by "?").
- The difference between the fifth and fourth difference is 12332 - 319 = 12013.

- Again, it is not immediately clear what pattern or rule is being followed by the differences between the differences. Let's examine the differences between the differences between the differences:

- The difference between the second and first difference is 248 - 53 = 195.
- The difference between the third and second difference is unknown (represented by "?").
- The difference between the fourth and third difference is 12013 - 248 = 11765.

- At this point, it becomes apparent that the differences between the differences are not following a simple pattern or rule. Therefore, it is unlikely that we can determine the missing term and complete the sequence based on the given information alone.